Efficacy and safety of surgical decompression in patients with cervical spondylotic myelopathy: results of the AOSpine North America prospective multi-center study

The significance of metabolic disease in degenerative cervical myelopathy: a systematic review

Introduction

Degenerative cervical myelopathy (DCM) is a form of chronic spinal cord injury, with a natural history of potential for progression over time. Whilst driven by mechanical stress on the spinal cord from degenerative and congenital pathology, the neurological phenotype of DCM is likely to be modified by multiple systemic factors. The role of metabolic factors is therefore of interest, particularly given that ischaemia is considered a key pathological mechanism of spinal cord injury. The objective was therefore to synthesise current evidence on the effect of metabolism on DCM susceptibility, severity, and surgical outcomes.

Methods

A systematic review in MEDLINE and Embase was conducted following PRISMA guidelines. Full-text papers in English, with a focus on DCM and metabolism, including diabetes, cardiovascular disease, anaemia, and lipid profile, were eligible for inclusion. Risk of methodological bias was assessed using the Joanna Briggs Institute (JBI) critical assessment tools. Quality assessments were performed using the GRADE assessment tool. Patient demographics, metabolic factors and the relationships between metabolism and spinal cord disease, spinal column disease and post-operative outcomes were assessed.

Results

In total, 8,523 papers were identified, of which 57 met criteria for inclusion in the final analysis. A total of 91% (52/57) of included papers assessed the effects of diabetes in relation to DCM, of which 85% (44/52) reported an association with poor surgical outcomes; 42% of papers (24/57) discussed the association between cardiovascular health and DCM, of which 88% (21/24) reported a significant association. Overall, DCM patients with diabetes or cardiovascular disease experienced greater perioperative morbidity and poorer neurological recovery. They were also more likely to have comorbidities such as obesity and hyperlipidaemia.

Conclusion

Metabolic factors appear to be associated with surgical outcomes in DCM. However, evidence for a more specific role in DCM susceptibility and severity is uncertain. The pathophysiology and natural history of DCM are critical research priorities; the role of metabolism is therefore a key area for future research focus.

Systematic review registration

https://www.crd.york.ac.uk/prospero/, identifier: CRD42021268814.

An innovative approach to assess spinal canal expansion following French-door cervical laminoplasty by intraoperative ultrasonography

OBJECTIVE

To investigate the feasibility and effectiveness of applying intraoperative ultrasound (IOUS) to evaluate spinal canal expansion in patients undergoing French-door cervical laminoplasty (FDCL).

MATERIALS AND METHODS

Twenty-five patients who underwent FDCL for multilevel degenerative cervical myelopathy were prospectively recruited. Formulae describing the relationship between laminoplasty opening angle (LOA) and laminoplasty opening size, the increase in sagittal canal diameter and the spinal canal area were deduced with trigonometric functions. The LOA was measured with IOUS imaging during surgery, and other spinal canal parameters were assessed. Actual spinal canal enlargement was verified on postoperative CT images. Linear correlation analysis and Bland‒Altman analysis were used to evaluate correlation and agreement between the intraoperative and postoperative measurements.

RESULTS

The LOA at C5 measured with IOUS was 27.54 ± 3.12°, and it was 27.23 ± 3.02° on postoperative CT imaging. Linear correlation analysis revealed a significant correlation between IOUS and postoperative CT measurements (r = 0.88; p < 0.01). Bland-Altman plots showed good agreement between these two methods, with a mean difference of 0.30°. For other spinal canal expansion parameter measurements, correlation analysis showed a moderate to a high degree of correlation (p < 0.01), and Bland-Altman analysis indicated good agreement.

CONCLUSION

In conclusion, during the French-door cervical laminoplasty procedure, application of IOUS can accurately evaluate spinal canal expansion. This innovative method may be helpful in improving surgical accuracy by enabling the operator to measure and determine canal enlargement during surgery, leading to ideal clinical outcomes and fewer postoperative complications.

CLINICAL RELEVANCE STATEMENT

The use of intraoperative ultrasonography to assess spinal canal expansion following French-door cervical laminoplasty may improve outcomes for patients undergoing this procedure by providing more accurate measurements of spinal canal expansion.

KEY POINTS

• Spinal canal expansion after French-door cervical laminoplasty substantially influences operative prognosis; insufficient or excessive lamina opening may result in unexpected outcomes. • Prediction of spinal canal expansion during surgery was previously impracticable, but based on this study, intraoperative ultrasonography offers an innovative approach and strongly agrees with postoperative CT measurement. • Since this is the first research to offer real-time canal expansion guidance for cervical laminoplasty, it may improve the accuracy of the operation and produce ideal clinical outcomes with fewer postoperative complications.

Systematic investigation of cerebellar functional alterations and their association with surgical outcomes in patients with degenerative cervical myelopathy: a resting-state fMRI study

OBJECTIVE

The aim of this study was to systematically investigate the changes in cerebellar neural activity and cerebellar-cortical functional connectivity (FC) in patients with degenerative cervical myelopathy (DCM) using resting-state functional magnetic resonance imaging (fMRI).

METHODS

In this study, we collected clinical data and resting-state fMRI data from 54 DCM patients and 50 healthy controls (HCs). We analyzed voxel-wise regional fMRI metrics, including amplitude of low frequency fluctuation (ALFF), fractional ALFF, regional homogeneity, functional connectivity density, and voxel-mirrored homotopic connectivity. In analysis 1, we examined the differences in regional fMRI metrics within the cerebellum between the DCM patient group and the healthy control group, as well as their correlation with preoperative neurological status and prognosis. In analysis 2, we investigated cerebellar-cortical functional connectivity differences between the two groups and their correlation with preoperative neurological status and prognosis. Lastly, in analysis 3, we explored the internetwork connectivity between the 'cerebellar-SMN' (sensorimotor network) system, examined the between-group differences, and investigated its correlation with preoperative neurological status and prognosis.

RESULTS

(1) Relative to HCs, DCM patients exhibited functional alterations in wide-spread cerebellar regions; (2) DCM patients exhibited altered cerebellar-cortical FC which was associated with the preoperative neurological status and prognosis; (3) DCM patients exhibited altered internetwork connectivity between 'cerebellar-SMN' system which was associated with duration of symptom.

CONCLUSION

Wide-spread cerebellar functional alterations occur in DCM pathogenesis and the deficits in cerebellar-SMN functional connectivity may be beneficial in future studies for predicting surgical outcomes in patients with DCM.

Elderly Patients Show Substantial Improvement in Health-Related Quality of Life After Surgery for Degenerative Cervical Myelopathy Despite Medical Frailty: An Ambispective Analysis of a Multicenter, International Data Set

BACKGROUND AND OBJECTIVES

We assessed the relationship between Modified Frailty Index-5 (mFI-5) and neurological outcomes, as well as health-related quality of life (HRQoL) measures, in elderly patients with degenerative cervical myelopathy (DCM) after surgery.

METHODS

Data from 3 major DCM trials (the Arbeitsgemeinschaft für Osteosynthesefragen Spine Cervical Spondylotic Myelopathy-North America, Cervical Spondylotic Myelopathy-International, and CSM-PROTECT studies) were combined, involving 1047 subjects with moderate to severe myelopathy. Patients older than 60 years with 6-month and 1-year postoperative data were analyzed. Neurological outcome was assessed using the modified Japanese Orthopaedic Association score, while HRQoL was measured using the 36-Item Short Form Health Survey (SF-36) (both Physical Component Summary [SF-36 PCS] and Mental Component Summary [SF-36 MCS] scores) and the Neck Disability Index. Frail (mFI ≥2) and nonfrail (mFI = 0-1) cohorts were compared using univariate paired statistics.

RESULTS

The final analysis included 261 patients (62.5% male), with a mean age of 71 years (95% CI 70.7-72). Frail patients (mFI ≥2) had lower baseline modified Japanese Orthopaedic Association scores (10.45 vs 11.96, P < .001), SF-36 PCS scores (32.01 vs 36.51, P < .001), and SF-36 MCS scores (39.32 vs 45.24, P < .001). At 6-month follow-up, SF-36 MCS improved by a mean (SD) of 7.19 (12.89) points in frail vs 2.91 (11.11) points in the nonfrail group (P = .016). At 1 year after surgery, frail patients showed greater improvement in both SF-36 PCS and SF-36 MCS composite scores compared with nonfrail patients (7.81 vs 4.49, P = .038, and 7.93 vs 3.01, P = .007, respectively). Bivariate regression analysis revealed that higher mFI-5 scores correlated with more substantial improvement in overall mental status at 6 months and 1 year (P = .024 and P = .009, respectively).

CONCLUSION

mFI-5 is a clinically helpful signature to reflect the HRQoL status among elderly patients with DCM. Despite preoperative medical frailty, elderly patients with DCM experience significant HRQoL improvement after surgery. These findings enable clinicians to identify elderly patients with modifiable comorbidities and provide informed counseling on anticipated outcomes.

LEVEL OF EVIDENCE

II.

Brain MRI changes in degenerative cervical myelopathy: a systematic review

BACKGROUND

Degenerative cervical myelopathy (DCM) is the most common cause of adult spinal cord dysfunction globally. Associated neurological symptoms and signs have historically been explained by pathobiology within the cervical spine. However, recent advances in imaging have shed light on numerous brain changes in patients with DCM, and it is hypothesised that these changes contribute to DCM pathogenesis. The aetiology, significance, and distribution of these supraspinal changes is currently unknown. The objective was therefore to synthesise all current evidence on brain changes in DCM.

METHODS

A systematic review was performed. Cross-sectional and longitudinal studies with magnetic resonance imaging on a cohort of patients with DCM were eligible. PRISMA guidelines were followed. MEDLINE and Embase were searched to 28th August 2023. Duplicate title/abstract screening, data extraction and risk of bias assessments were conducted. A qualitative synthesis of the literature is presented as per the Synthesis Without Meta-Analysis (SWiM) reporting guideline. The review was registered with PROSPERO (ID: CRD42022298538).

FINDINGS

Of the 2014 studies that were screened, 47 studies were identified that used MRI to investigate brain changes in DCM. In total, 1500 patients with DCM were included in the synthesis, with a mean age of 53 years. Brain alterations on MRI were associated with DCM both before and after surgery, particularly within the sensorimotor network, visual network, default mode network, thalamus and cerebellum. Associations were commonly reported between brain MRI alterations and clinical measures, particularly the Japanese orthopaedic association (JOA) score. Risk of bias of included studies was low to moderate.

INTERPRETATION

The rapidly expanding literature provides mounting evidence for brain changes in DCM. We have identified key structures and pathways that are altered, although there remains uncertainty regarding the directionality and clinical significance of these changes. Future studies with greater sample sizes, more detailed phenotyping and longer follow-up are now needed.

FUNDING

ODM is supported by an Academic Clinical Fellowship at the University of Cambridge. BMD is supported by an NIHR Clinical Doctoral Fellowship at the University of Cambridge (NIHR300696). VFJN is supported by an NIHR Rosetrees Trust Advanced Fellowship (NIHR302544). This project was supported by an award from the Rosetrees Foundation with the Storygate Trust (A2844).

Early surgery compared to nonoperative management for mild degenerative cervical myelopathy: a cost-utility analysis

BACKGROUND CONTEXT

Degenerative cervical myelopathy (DCM) is a form of acquired spinal cord compression and contributes to reduced quality of life secondary to neurological dysfunction and pain. There remains uncertainty regarding optimal management for individuals with mild myelopathy. Specifically, owing to lacking long-term natural history studies in this population, we do not know whether these individuals should be treated with initial surgery or observation.

PURPOSE

We sought to perform a cost-utility analysis to examine early surgery for mild degenerative cervical myelopathy from the healthcare payer perspective.

STUDY DESIGN/SETTING

We utilized data from the prospective observational cohorts included in the Cervical Spondylotic Myelopathy AO Spine International and North America studies to determine health related quality of life estimates and clinical myelopathy outcomes.

PATIENT SAMPLE

We recruited all patients that underwent surgery for DCM enrolled in the Cervical Spondylotic Myelopathy AO Spine International and North America studies between December 2005 and January 2011.

OUTCOME MEASURES

Clinical assessment measures were obtained using the Modified Japanese Orthopedic Association scale and health-related quality of life measures were obtained using the Short Form-6D utility score at baseline (preoperative), 6 months, 12 months and 24 months postsurgery. Cost measures inflated to January 2015 values were obtained using pooled estimates from the hospital payer perspective for surgical patients.

METHODS

We employed a Markov state transition model with Monte Carlo microsimulation using a lifetime horizon to obtain an incremental cost utility ratio associated with early surgery for mild myelopathy. Parameter uncertainty was assessed through deterministic means using one-way and two-way sensitivity analyses and probabilistically using parameter estimate distributions with microsimulation (10,000 trials). Costs and utilities were discounted at 3% per annum.

RESULTS

Initial surgery for mild degenerative cervical myelopathy was associated with an incremental lifetime increase of 1.26 quality-adjusted life years (QALY) compared to observation. The associated cost incurred to the healthcare payer over a lifetime horizon was $12,894.56, resulting in a lifetime incremental cost-utility ratio of $10,250.71/QALY. Utilizing a willingness to pay threshold in keeping with the World Health Organization definition of "very cost-effective" ($54,000 CDN), the probabilistic sensitivity analysis demonstrated that 100% of cases were cost-effective.

CONCLUSIONS

Surgery compared to initial observation for mild degenerative cervical myelopathy was cost-effective from the Canadian healthcare payer perspective and was associated with lifetime gains in health-related quality of life.

Subclinical respiratory dysfunction and impaired ventilatory adaptation in degenerative cervical myelopathy

Degenerative cervical myelopathy (DCM) is a debilitating neurological condition characterized by chronic compression of the cervical spinal cord leading to impaired upper and lower limb function. Despite damage to areas of the cervical spinal cord that house the respiratory network, respiratory dysfunction is not a common symptom of DCM. However, DCM may be associated with respiratory dysfunction, and this can affect the ventilatory response to respiratory challenges during emergence from anesthesia, exercise, or pulmonary disease. Surgical spinal cord decompression, which is the primary treatment for DCM, leads to improved sensorimotor function in DCM; yet its impact on respiratory function is unknown. Here, using a clinically relevant model of DCM, we evaluate respiratory function during disease progression and assess adaptive ventilation to hypercapnic challenge before and after surgical intervention. We show that despite significant and progressive forelimb and locomotor deficits, there was no significant decline in eupneic ventilation from the early to late phases of spinal cord compression. Additionally, for the first time, we demonstrate that despite normal ventilation under resting conditions, DCM impairs acute adaptive ventilatory ability in response to hypercapnia. Remarkably, akin to DCM patients, surgical decompression treatment improved sensorimotor function in a subset of mice. In contrast, none of the mice that underwent surgical decompression recovered their ability to respond to hypercapnic ventilatory challenge. These findings underscore the impact of chronic spinal cord compression on respiratory function, highlighting the challenges associated with ventilatory response to respiratory challenges in individuals with DCM. This research highlights the impact of cervical spinal cord compression on respiratory dysfunction in DCM, as well as the persistence of adaptive ventilatory dysfunction after surgical spinal cord decompression. These results indicate the need for additional interventions to enhance recovery of respiratory function after surgery for DCM.

Developing predictive models for surgical outcomes in patients with degenerative cervical myelopathy: a comparison of statistical and machine learning approaches

BACKGROUND CONTEXT

Machine learning (ML) is widely used to predict the prognosis of numerous diseases.

PURPOSE

This retrospective analysis aimed to develop a prognostic prediction model using ML algorithms and identify predictors associated with poor surgical outcomes in patients with degenerative cervical myelopathy (DCM).

STUDY DESIGN

A retrospective study.

PATIENT SAMPLE

A total of 406 symptomatic DCM patients who underwent surgical decompression were enrolled and analyzed from three independent medical centers.

OUTCOME MEASURES

We calculated the area under the curve (AUC), classification accuracy, sensitivity, and specificity of each model.

METHODS

The Japanese Orthopedic Association (JOA) score was obtained before and 1 year following decompression surgery, and patients were grouped into good and poor outcome groups based on a cut-off value of 60% based on a previous study. Two datasets were fused for training, 1 dataset was held out as an external validation set. Optimal feature-subset and hyperparameters for each model were adjusted based on a 2,000-resample bootstrap-based internal validation via exhaustive search and grid search. The performance of each model was then tested on the external validation set.

RESULTS

The Support Vector Machine (SVM) model showed the highest predictive accuracy compared to other methods, with an AUC of 0.82 and an accuracy of 75.7%. Age, sex, disease duration, and preoperative JOA score were identified as the most commonly selected features by both the ML and statistical models. Grid search optimization for hyperparameters successfully enhanced the predictive performance of each ML model, and the SVM model still had the best performance with an AUC of 0.93 and an accuracy of 86.4%.

CONCLUSIONS

Overall, the study demonstrated that ML classifiers such as SVM can effectively predict surgical outcomes for patients with DCM while identifying associated predictors in a multivariate manner.

Validating the preoperative Japanese Core Outcome Measures Index for the Neck and comparing quality of life in patients with cervical spondylotic myelopathy and ossification of the posterior longitudinal ligament by the patient-reported outcome measures

PURPOSE

This cross-sectional study serves two main purposes. Firstly, it aims to validate the preoperative Japanese Core Outcome Measures Index for the Neck (COMI-Neck) in patients with cervical spondylotic myelopathy (CSM) and ossification of the posterior longitudinal ligament (OPLL). Secondly, it seeks to elucidate differences in preoperative quality of life (QOL) between these two cervical pathologies using patient-reported outcome measures (PROMs).

METHODS

A total of 103 preoperative patients (86 with CSM and 17 with OPLL) scheduled for cervical spine surgery were included in the study. Validated PROMs, including the Japanese COMI-Neck, Neck Disability Index (NDI), EuroQol-5 Dimension-3 level (EQ-5D-3L), and SF-12v2, were used to assess QOL. Baseline demographic and clinical data were collected, and statistical analyses were performed to compare the PROMs between CSM and OPLL groups.

RESULTS

The Japanese COMI-Neck demonstrated good construct validity, with positive correlations with NDI and negative correlations with EQ-5D-3L and SF-12v2. Comparison of preoperative PROMs between CSM and OPLL groups revealed differences in age, body mass index, and EQ-5D-3L scores. The CSM group had higher NDI scores for concentration and lower EQ-5D-3L scores for self-care compared to the OPLL group.

CONCLUSIONS

This study validated the preoperative Japanese COMI-Neck in CSM and OPLL patients and identified specific QOL issues associated with each condition. The findings highlight the importance of considering disease-specific QOL and tailoring treatment plans accordingly. Further research should include postoperative assessments and a more diverse population to enhance generalizability.

Developing Mixed-effects Models to Optimize Prediction of Postoperative Outcomes in a Modern Sample of Over 450,000 Patients Undergoing Elective Cervical Spine Fusion Surgery

STUDY DESIGN

A retrospective cohort.

OBJECTIVE

We utilize big data and modeling techniques to create optimized comorbidity indices for predicting postoperative outcomes following cervical spine fusion surgery.

SUMMARY OF BACKGROUND DATA

Cervical spine decompression and fusion surgery are commonly used to treat degenerative cervical spine pathologies. However, there is a paucity of high-quality data defining the optimal comorbidity indices specifically in patients undergoing cervical spine fusion surgery.

METHODS

Using data from 2016 to 2019, we queried the Nationwide Readmissions Database (NRD) to identify individuals who had received cervical spine fusion surgery. The Johns Hopkins Adjusted Clinical Groups (JHACG) frailty-defining indicator was used to assess frailty. To measure the level of comorbidity, Elixhauser Comorbidity Index (ECI) scores were queried. Receiver operating characteristic curves were developed utilizing comorbidity indices as predictor variables for pertinent complications such as mortality, nonroutine discharge, top-quartile cost, top-quartile length of stay, and 1-year readmission.

RESULTS

A total of 453,717 patients were eligible. Nonroutine discharges occurred in 93,961 (20.7%) patients. The mean adjusted all-payer cost for the procedure was $22,573.14±18,274.86 (top quartile: $26,775.80) and the mean length of stay was 2.7±4.4 days (top quartile: 4.7 d). There were 703 (0.15%) mortalities and 58,254 (12.8%) readmissions within 1 year postoperatively. Models using frailty+ECI as primary predictors consistently outperformed the ECI-only model with statistically significant P -values for most of the complications assessed. Cost and mortality were the only outcomes for which this was not the case, as frailty outperformed both ECI and frailty+ECI in cost ( P <0.0001 for all) and frailty+ECI performed as well as ECI alone in mortality ( P =0.10).

CONCLUSIONS

Our data suggest that frailty+ECI may most accurately predict clinical outcomes in patients receiving cervical spine fusion surgery. These models may be used to identify high-risk populations and patients who may necessitate greater resource utilization following elective cervical spinal fusion.

Pathophysiology and surgical decision-making in central cord syndrome and degenerative cervical myelopathy: correcting the somatotopic fallacy

Our understanding of Central Cord Syndrome (CCS), a form of incomplete spinal cord injury characterized by disproportionate upper extremity weakness, is evolving. Recent advances challenge the traditional somatotopic model of corticospinal tract organization within the spinal cord, suggesting that CCS is likely a diffuse injury rather than focal lesion. Diagnostic criteria for CCS lack consensus, and varied definitions impact patient identification and treatment. Evidence has mounted for early surgery for CCS, although significant variability persists in surgical timing preferences among practitioners. A demographic shift toward an aging population has increased the overlap between CCS and Degenerative Cervical Myelopathy (DCM). Understanding this intersection is crucial for comprehensive patient care. Assessment tools, including quantitative measures and objective evaluations, aid in distinguishing CCS from DCM. The treatment landscape for CCS in the context of pre-existing DCM is complex, requiring careful consideration of pre-existing neurologic injury, patient factors, and injury factors. This review synthesizes emerging evidence, outlines current guidelines in diagnosis and management, and emphasizes the need for ongoing research to refine our understanding and treatment strategies for this evolving patient population.

Toward Shared Decision-Making in Degenerative Cervical Myelopathy: Protocol for a Mixed Methods Study

BACKGROUND

Health care decisions are a critical determinant in the evolution of chronic illness. In shared decision-making (SDM), patients and clinicians work collaboratively to reach evidence-based health decisions that align with individual circumstances, values, and preferences. This personalized approach to clinical care likely has substantial benefits in the oversight of degenerative cervical myelopathy (DCM), a type of nontraumatic spinal cord injury. Its chronicity, heterogeneous clinical presentation, complex management, and variable disease course engenders an imperative for a patient-centric approach that accounts for each patient's unique needs and priorities. Inadequate patient knowledge about the condition and an incomplete understanding of the critical decision points that arise during the course of care currently hinder the fruitful participation of health care providers and patients in SDM. This study protocol presents the rationale for deploying SDM for DCM and delineates the groundwork required to achieve this.

OBJECTIVE

The study's primary outcome is the development of a comprehensive checklist to be implemented upon diagnosis that provides patients with essential information necessary to support their informed decision-making. This is known as a core information set (CIS). The secondary outcome is the creation of a detailed process map that provides a diagrammatic representation of the global care workflows and cognitive processes involved in DCM care. Characterizing the critical decision points along a patient's journey will allow for an effective exploration of SDM tools for routine clinical practice to enhance patient-centered care and improve clinical outcomes.

METHODS

Both CISs and process maps are coproduced iteratively through a collaborative process involving the input and consensus of key stakeholders. This will be facilitated by Myelopathy.org, a global DCM charity, through its Research Objectives and Common Data Elements for Degenerative Cervical Myelopathy community. To develop the CIS, a 3-round, web-based Delphi process will be used, starting with a baseline list of information items derived from a recent scoping review of educational materials in DCM, patient interviews, and a qualitative survey of professionals. A priori criteria for achieving consensus are specified. The process map will be developed iteratively using semistructured interviews with patients and professionals and validated by key stakeholders.

RESULTS

Recruitment for the Delphi consensus study began in April 2023. The pilot-testing of process map interview participants started simultaneously, with the formulation of an initial baseline map underway.

CONCLUSIONS

This protocol marks the first attempt to provide a starting point for investigating SDM in DCM. The primary work centers on developing an educational tool for use in diagnosis to enable enhanced onward decision-making. The wider objective is to aid stakeholders in developing SDM tools by identifying critical decision junctures in DCM care. Through these approaches, we aim to provide an exhaustive launchpad for formulating SDM tools in the wider DCM community.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/46809.

The Impact of Preoperative Symptom Duration on Patient Outcomes After Posterior Cervical Decompression and Fusion

STUDY DESIGN

Retrospective Cohort Study.

OBJECTIVES

To determine if decreased preoperative symptom duration is associated with greater clinical improvement in function and myelopathic symptoms after posterior cervical decompression and fusion (PCDF).

METHODS

All patients over age 18 who underwent primary PCDF for cervical myelopathy or myeloradiculopathy at a single institution between 2014 and 2020 were retrospectively identified. Patient demographics, surgical characteristics, duration of symptoms, and preoperative and postoperative patient reported outcomes measures (PROMs) including modified Japanese Orthopaedic Association (mJOA), Neck Disability Index (NDI), Visual Analogue Scale (VAS) Neck, VAS Arm, and SF-12 were collected. Univariate and multivariate analyses were performed to compare change in PROMs and minimum clinically important difference achievement (%MCID) between symptom duration groups (< 6 months, 6 months-2 years, > 2 years).

RESULTS

Preoperative symptom duration groups differed significantly by sex and smoking status. Patients with < 6 months of preoperative symptoms improved significantly in all PROMs. Patients with 6 months-2 years of preoperative symptoms did not improve significantly in mJOA, Physical Component Scores (PCS), or NDI. Patients with > 2 years of symptoms failed to demonstrate significant improvement in mJOA, NDI, or Mental Component Scores (MCS). Univariate analysis demonstrated significantly decreased improvement in mJOA with longer symptom durations. Increased preoperative symptom duration trended toward decreased %MCID for mJOA and MCS. Regression analysis demonstrated that preoperative symptom duration of > 2 years relative to < 6 months predicted decreased improvement in mJOA and NDI and decreased MCID achievement for mJOA and MCS.

CONCLUSION

Increased duration of preoperative symptoms (> 2 years) before undergoing PCDF was associated with decreased postoperative improvement in myelopathic symptoms.

Blood-spinal cord barrier disruption in degenerative cervical myelopathy

Degenerative cervical myelopathy (DCM) is the most prevalent cause of spinal cord dysfunction in the aging population. Significant neurological deficits may result from a delayed diagnosis as well as inadequate neurological recovery following surgical decompression. Here, we review the pathophysiology of DCM with an emphasis on how blood-spinal cord barrier (BSCB) disruption is a critical yet neglected pathological feature affecting prognosis. In patients suffering from DCM, compromise of the BSCB is evidenced by elevated cerebrospinal fluid (CSF) to serum protein ratios and abnormal contrast-enhancement upon magnetic resonance imaging (MRI). In animal model correlates, there is histological evidence of increased extravasation of tissue dyes and serum contents, and pathological changes to the neurovascular unit. BSCB dysfunction is the likely culprit for ischemia-reperfusion injury following surgical decompression, which can result in devastating neurological sequelae. As there are currently no therapeutic approaches specifically targeting BSCB reconstitution, we conclude the review by discussing potential interventions harnessed for this purpose.

Factors Influencing Surgical Decision-Making in the Posterior Laminectomy With Fixation for Degenerative Cervical Myelopathy (POLYFIX-DCM) Trial: Survey Study

BACKGROUND

Degenerative cervical myelopathy (DCM) is estimated to affect 2% of the adult population. DCM occurs when degenerative processes cause compression and injure the spinal cord. Surgery to remove the stress caused by the compression of the spinal cord is the mainstay of treatment, with a range of techniques in use. Although various factors are described to inform the selection of these techniques, there needs to be more consensus and limited comparative evidence.

OBJECTIVE

The main objective of this survey was to explore the variation of practice and decision-making, with a focus on laminectomy versus laminectomy and fusion in posterior surgery of the cervical spine. We present the results of a survey conducted among the principal investigators (PIs) of the National Institute for Health and Care Research (NIHR) randomized controlled trial on posterior laminectomy with fixation for degenerative cervical myelopathy (POLYFIX-DCM).

METHODS

A series of 7 cases were shared with 24 PIs using SurveyMonkey. Each case consisted of a midsagittal T2-weighted magnetic resonance imaging and lateral cervical x-rays in flexion and extension. Surgeons were asked if their preferred approach was anterior or posterior. If posterior, they were asked whether they preferred to instrument and whether they had the equipoise to randomize in the NIHR POLYFIX-DCM trial. Variability in decision-making was then explored using factors reported to inform decision-making, such as alignment, location of compression, number of levels operated, presence of mobile spondylolisthesis, and patient age.

RESULTS

The majority of PIs (16/30, 53%) completed the survey. Overall, PIs favored a posterior approach (12/16, 75%) with instrumentation (75/112, average 66%) and would randomize (67/112, average 62%) most cases. Factors reported to inform decision-making poorly explained variability in responses in both univariate testing and with a multivariate model (R2=0.1). Only surgeon experience of more than 5 years and orthopedic specialty training background were significant predictors, both associated with an anterior approach (odds ratio [OR] 1.255; P=.02 and OR 1.344; P=.007, respectively) and fusion for posterior procedures (OR 0.628; P<.001 and OR 1.344; P<.001, respectively). Surgeon experience also significantly affected the openness to randomize, with those with more than 5 years of experience less likely to randomize (OR -0.68; P<.001).

CONCLUSIONS

In this representative sample of spine surgeons participating in the POLYFIX-DCM trial as investigators, there is no consensus on surgical strategy, including the role of instrumented fusion following posterior decompression. Overall, this study supports the view that there appears to be a clinical equipoise, and conceptually, a randomized controlled trial appears feasible, which sets the scene for the NIHR POLYFIX-DCM trial.

EARLY COMPLICATIONS OF SURGICAL TREATMENT OF CERVICAL SPONDYLOTIC MYELOPATHY

Objective

To evaluate the early postoperative complications associated with the surgical approach of the cervical spine of patients with cervical spondylotic myelopathy (CSM), comparing the anterior surgical, the posterior surgical, and the combined approaches.

Methods

This is a retrospective study based on a database with 169 patients. Demographic data, such as gender and age, and surgical data, such as surgical approach, number of segments with arthrodesis, surgical time, and complications, were evaluated. Complications were divided into major (deep surgical wound infection, intercurrence with the implant, early new compression, and heart failure) and minor (dysphagia, superficial infection, pain, urinary intercurrence, neuropraxia of the C5 root, acute confusional state, and surgical wound hematoma).

Results

This included 169 patients, 57 women (33.7%) and 112 men (66.2%). Age ranged from 21 to 87 years, with a mean of 56.48 (± 11) years. Of these, 52 (30.8%) underwent the anterior approach; 111 (65.7%), the posterior approach; and 6 (3.5%), the combined approach.

Conclusion

As in the literature, we evinced dysphagia, pain, and superficial infection of the surgical wound as the most frequent postoperative complications. However, it was impossible to establish a statistical relationship between the incidence of complications and surgical time, access route, and number of fixed segments. Level of Evidence III, Retrospective Comparative Study.

Risk Factors for Cervical Deformity After Posterior Cervical Decompression Surgery: A Multicenter Study

STUDY DESIGN

Retrospective multicenter study.

OBJECTIVE

Posterior decompression surgery for cervical spondylotic myelopathy (CSM) and ossification of the posterior longitudinal ligament (OPLL) is a common surgery; however, it can cause postoperative cervical deformity (CD). The purpose of this study was to investigate the risk factors for CD.

METHODS

The participants were 193 patients underwent laminoplasty or laminectomy for CSM or OPLL. CD was defined as a C2-7 sagittal vertical axis (SVA) ≥ 40 mm or a cervical lordosis angle (CL) ≤ -10°. The participants were divided into 2 groups: NCD (without CD before surgery), CD (with CD before surgery). NCD group was divided based on the presence of CD 1 year after surgery as follows: postoperative CD (PCD) and no PCD (NPCD).

RESULTS

There were 153 patients (NCD), 40 (CD), 126 (NPCD), and 27 (PCD). There was significant difference in the number of decompressed lamina (NPCD: PCD = 4.1:4.5), the presence of C2 decompression (2: 11%), and C5 palsy (0: 11%). The risk factors for onset of CD, PCD, and CL ≤ -10° as assessed by multiple logistic regression analysis were preoperative C2-7 SVA ≥ 30 mm (odds ratio [OR]: 19.0), decompression of C2 or C7 lamina (OR 3.1), and preoperative CL ≤ 2° (OR 42.0), respectively.

CONCLUSIONS

To prevent postoperative CD, it is important to avoid decompression of the C2 or C7 lamina. Moreover, in case with C2-7 SVA ≥ 30 mm or CL ≤ 2° before surgery, it is important to explain the risks and consider adding fusion surgery.

Integration of MRI and somatosensory evoked potentials facilitate diagnosis of spinal cord compression

This study aimed to integrate magnetic resonance imaging (MRI) and related somatosensory evoked potential (SSEP) features to assist in the diagnosis of spinal cord compression (SCC). MRI scans were graded from 0 to 3 according to the changes in the subarachnoid space and scan signals to confirm differences in SCC levels. The amplitude, latency, and time-frequency analysis (TFA) power of preoperative SSEP features were extracted and the changes were used as standard judgments to detect neurological function changes. Then the patient distribution was quantified according to the SSEP feature changes under the same and different MRI compression grades. Significant differences were found in the amplitude and TFA power between MRI grades. We estimated three degrees of amplitude anomalies and power loss under each MRI grade and found the presence or absence of power loss occurs after abnormal changes in amplitude only. For SCC, few integrated approach combines the advantages of both MRI and evoked potentials. However, integrating the amplitude and TFA power changes of SSEP features with MRI grading can help in the diagnosis and speculate progression of SCC.

Blood spinal cord barrier disruption recovers in patients with degenerative cervical myelopathy after surgical decompression: a prospective cohort study

The pathophysiology of degenerative cervical myelopathy (DCM) is characterized by chronic compression-induced damage to the spinal cord leading to secondary harm such as disruption of the blood spinal cord barrier (BSCB). It is therefore the purpose of this study to analyze BSCB disruption in pre- and postoperative DCM patients and to correlate those with the clinical status and postoperative outcome. This prospectively controlled cohort included 50 DCM patients (21 female; 29 male; mean age: 62.9 ± 11.2 years). As neurological healthy controls, 52 (17 female; 35 male; mean age 61.8 ± 17.3 years) patients with thoracic abdominal aortic aneurysm (TAAA) and indication for open surgery were included. All patients underwent a neurological examination and DCM-associated scores (Neck Disability Index, modified Japanese Orthopaedic Association Score) were assessed. To evaluate the BSCB status, blood and cerebrospinal fluid (CSF) samples (lumbar puncture or CSF drainage) were taken preoperatively and in 15 DCM patients postoperatively (4 female; 11 male; mean age: 64.7 ± 11.1 years). Regarding BSCB disruption, CSF and blood serum were examined for albumin, immunoglobulin (Ig) G, IgA and IgM. Quotients for CSF/serum were standardized and calculated according to Reiber diagnostic criteria. Significantly increased preoperative CSF/serum quotients were found in DCM patients as compared to control patients: Albumin_Q (p < .001), IgA_Q (p < .001) and IgG_Q (p < .001). IgM_Q showed no significant difference (T = - 1.15, p = .255). After surgical decompression, neurological symptoms improved in DCM patients, as shown by a significantly higher postoperative mJOA compared to the preoperative score (p = .001). This neurological improvement was accompanied by a significant change in postoperative CSF/serum quotients for Albumin (p = .005) and IgG (p = .004) with a trend of a weak correlation between CSF markers and neurological recovery. This study further substantiates the previous findings, that a BSCB disruption in DCM patients is evident. Interestingly, surgical decompression appears to be accompanied by neurological improvement and a reduction of CSF/serum quotients, implying a BSCB recovery. We found a weak association between BSCB recovery and neurological improvement. A BSCB disruption might be a key pathomechanism in DCM patients, which could be relevant to treatment and clinical recovery.

Targeting earlier diagnosis: What symptoms come first in Degenerative Cervical Myelopathy?

BACKGROUND

Degenerative cervical myelopathy (DCM) is a common and disabling condition. Early effective treatment is limited by late diagnosis. Conventional descriptions of DCM focus on motor and sensory limb disability, however, recent work suggests the true impact is much broader. This study aimed to characterise the symptomatic presentation of DCM from the perspective of people with DCM and determine whether any of the reported symptoms, or groups of symptoms, were associated with early diagnosis.

METHODS

An internet survey was developed, using an established list of patient-reported effects. Participants (N = 171) were recruited from an online community of people with DCM. Respondents selected their current symptoms and primary presenting symptom. The relationship of symptoms and their relationship to time to diagnosis were explored. This included symptoms not commonly measured today, termed 'non-conventional' symptoms.

RESULTS

All listed symptoms were experienced by >10% of respondents, with poor balance being the most commonly reported (84.2%). Non-conventional symptoms accounted for 39.7% of symptomatic burden. 55.4% of the symptoms were reported as an initial symptom, with neck pain the most common (13.5%). Non-conventional symptoms accounted for 11.1% of initial symptoms. 79.5% of the respondents were diagnosed late (>6 months). Heavy legs was the only initial symptom associated with early diagnosis.

CONCLUSIONS

A comprehensive description of the self-reported effects of DCM has been established, including the prevalence of symptoms at disease presentation. The experience of DCM is broader than suggested by conventional descriptions and further exploration of non-conventional symptoms may support earlier diagnosis.

Targeting patient recovery priorities in degenerative cervical myelopathy: design and rationale for the RECEDE-Myelopathy trial-study protocol

INTRODUCTION

Degenerative cervical myelopathy (DCM) is a common and disabling condition of symptomatic cervical spinal cord compression secondary to degenerative changes in spinal structures leading to a mechanical stress injury of the spinal cord. RECEDE-Myelopathy aims to test the disease-modulating activity of the phosphodiesterase 3/phosphodiesterase 4 inhibitor Ibudilast as an adjuvant to surgical decompression in DCM.

METHODS AND ANALYSIS

RECEDE-Myelopathy is a multicentre, double-blind, randomised, placebo-controlled trial. Participants will be randomised to receive either 60-100 mg Ibudilast or placebo starting within 10 weeks prior to surgery and continuing for 24 weeks after surgery for a maximum of 34 weeks. Adults with DCM, who have a modified Japanese Orthopaedic Association (mJOA) score 8-14 inclusive and are scheduled for their first decompressive surgery are eligible for inclusion. The coprimary endpoints are pain measured on a visual analogue scale and physical function measured by the mJOA score at 6 months after surgery. Clinical assessments will be undertaken preoperatively, postoperatively and 3, 6 and 12 months after surgery. We hypothesise that adjuvant therapy with Ibudilast leads to a meaningful and additional improvement in either pain or function, as compared with standard routine care.

STUDY DESIGN

Clinical trial protocol V.2.2 October 2020.

ETHICS AND DISSEMINATION

Ethical approval has been obtained from HRA-Wales.The results will be presented at an international and national scientific conferences and in a peer-reviewed journals.

TRIAL REGISTRATION NUMBER

ISRCTN Number: ISRCTN16682024.

A clinical model to predict postoperative improvement in sub-domains of the modified Japanese Orthopedic Association score for degenerative cervical myelopathy

PURPOSE

The modified Japanese Orthopedic Association (mJOA) score consists of six sub-domains and is used to quantify the severity of cervical myelopathy. The current study aimed to assess for predictors of postoperative mJOA sub-domains scores following elective surgical management for patients with cervical myelopathy and develop the first clinical prediction model for 12-month mJOA sub-domain scores.Please confirm if the author names are presented accurately and in the correct sequence (given name, middle name/initial, family name). Author 1 Given name: [Byron F.] Last name [Stephens], Author 2 Given name: [Lydia J.] Last name [McKeithan], Author 3 Given name: [W. Hunter] Last name [Waddell], Author 4 Given name: [Anthony M.] Last name [Steinle], Author 5 Given name: [Wilson E.] Last name [Vaughan], Author 6 Given name: [Jacquelyn S.] Last name [Pennings], Author 7 Given name: [Jacquelyn S.] Last name [Pennings], Author 8 Given name: [Scott L.] Last name [Zuckerman], Author 9 Given name: [Kristin R.] Last name [Archer], Author 10 Given name: [Amir M.] Last name [Abtahi] Also, kindly confirm the details in the metadata are correct.Last Author listed should be Kristin R. Archer METHODS: A multivariable proportional odds ordinal regression model was developed for patients with cervical myelopathy. The model included patient demographic, clinical, and surgery covariates along with baseline sub-domain scores. The model was internally validated using bootstrap resampling to estimate the likely performance on a new sample of patients.

RESULTS

The model identified mJOA baseline sub-domains to be the strongest predictors of 12-month scores, with numbness in legs and ability to walk predicting five of the six mJOA items. Additional covariates predicting three or more items included age, preoperative anxiety/depression, gender, race, employment status, duration of symptoms, smoking status, and radiographic presence of listhesis. Surgical approach, presence of motor deficits, number of surgical levels involved, history of diabetes mellitus, workers' compensation claim, and patient insurance had no impact on 12-month mJOA scores.

CONCLUSION

Our study developed and validated a clinical prediction model for improvement in mJOA scores at 12 months following surgery. The results highlight the importance of assessing preoperative numbness, walking ability, modifiable variables of anxiety/depression, and smoking status. This model has the potential to assist surgeons, patients, and families when considering surgery for cervical myelopathy.

LEVEL OF EVIDENCE

Level III.

Does Diabetes Affect the Surgical Outcomes in Cases With Cervical Ossification of the Posterior Longitudinal Ligament? A Multicenter Study From Asia Pacific Spine Study Group

STUDY DESIGN

Retrospective multicenter study.

OBJECTIVES

To evaluate the surgical outcomes of cervical ossification of the posterior longitudinal ligament (OPLL) in diabetes mellitus (DM) patients.

METHODS

Approximately 253 cervical OPLL patients who underwent surgical decompression with or without fixation were registered at 4 institutions in 3 Asian countries. They were followed up for at least 2 years. Demographics, imaging, and surgical information were collected, and cervical Japanese Orthopaedic Association (JOA) scores and the visual analog scale (VAS) for the neck were used for evaluation.

RESULTS

Forty-seven patients had DM, showing higher hypertension and cardiovascular disease prevalence. Although they presented worse preoperative JOA scores than non-DM patients (10.5 ± 3.1 vs. 11.8 ± 3.2; P = 0.01), the former showed comparable neurologic recovery at the final follow-up (13.9 ± 2.9 vs. 14.2 ± 2.6; P = 0.41). No correlation was noted between the hemoglobin A1c level in the DM group and the pre- and postoperative JOA scores. No significant difference was noted in VAS scores between the groups at pre- and postsurgery. Regarding perioperative complications, DM patients presented a higher C5 palsy frequency (14.9% vs. 5.8%; P = 0.04). A similar trend was observed when surgical procedure was limited to laminoplasty.

CONCLUSIONS

This is the first multicenter Asian study to evaluate the impact of DM on cervical OPLL patients. Surgical results were favorable even in DM cases, regardless of preoperative hemoglobin A1c levels or operative procedures. However, caution is warranted for the occurrence of C5 palsy after surgery.

Clinical Improvements in Myelopathy Result in Improved Patient-Reported Outcomes Following Anterior Cervical Discectomy and Fusion

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

To determine if myelopathy severity predicted the magnitude of improvement in health-related quality of life metrics following anterior cervical discectomy and fusion (ACDF).

SUMMARY OF BACKGROUND DATA

Surgery for myelopathy is primarily performed to halt disease progression. However, it is still controversial if these patients can expect significant health-related quality-of life improvements following ACDF. We explore the relationship between modified Japanese Orthopaedic Association (mJOA) improvements and its effect on other health-related quality-of life metrics.

MATERIALS AND METHODS

Patients undergoing ACDF for myelopathy were grouped based on preoperative mJOA scores into mild (15-17), moderate (12-14), and severe (<12) groups. Patients were subsequently categorized based on if they attained the minimum clinically detectable improvement (MCID) threshold for mJOA. Multivariate linear regression was performed to determine the magnitude of improvement in ∆patient-reported outcome measures.

RESULTS

A total of 374 patients were identified for inclusion. Of those, 169 (45.2%) had mild myelopathy, 125 (33.4%) had moderate, and 80 (21.4%) had severe myelopathy. Only the moderate and severe groups had significant improvements in mJOA following surgery (mild: P =0.073, moderate: P <0.001, severe: P <0.001). There were no significant differences in the magnitude of improvement for any patient-reported outcome measure based on myelopathy severity, except for mJOA (mild: 0.27, moderate: 1.88, severe: 3.91; P <0.001). Patients meeting the MCID for mJOA had better ∆Short-Form 12 Mental Component Score (3.29 vs. -0.21, P =0.007), ∆Short-Form 12 Physical Component Score (6.82 vs. 1.96, P <0.001), ∆Visual Analog Scale Neck (-3.11 vs. -2.17, P =0.001), ∆Visual Analog Scale Arm (-2.92 vs. -1.48, P <0.001), ∆Neck Disability Index (-18.35 vs. -7.86, P <0.001), and ∆mJOA (3.38 vs. -0.56, P <0.001) compared with patients who did not.

CONCLUSIONS

Worse baseline myelopathy severity predicts worse postoperative outcomes. However, baseline myelopathy severity is not predictive of the magnitude of postoperative improvement with the exception of mJOA. Patients who attain MCID improvement in mJOA had greater postoperative improvement for other health-related quality of life metrics.

Determinants of quality of life in degenerative cervical myelopathy: a systematic review

BACKGROUND

Degenerative cervical myelopathy (DCM) is the most common cause of chronic, progressive spinal cord impairment worldwide. Patients experience substantial pain, functional neurological decline and disability. Health-related quality of life (HRQoL) appears to be particularly poor, even when compared to other chronic diseases. However, the determinants of HRQoL are poorly understood. The objective was to perform a systematic review of the determinants of quality of life of people with DCM.

METHODS

A systematic search was conducted in MEDLINE and Embase following PRISMA 2020 guidelines (PROSPERO CRD42018115675). Full-text papers in English, exclusively studying DCM, published before 26 March 2020 were eligible for inclusion and were assessed using the Newcastle-Ottawa Scale and the Cochrane Risk of Bias 2 (RoB 2) tool. Study sample characteristics, patient demographics, cohort type, HRQoL instrument utilised, HRQoL score, and relationships of HRQoL with other variables were qualitatively synthesised.

RESULTS

A total of 1176 papers were identified; 77 papers and 13,572 patients were included in the final analysis. A total of 96% of papers studied surgical cohorts and 86% utilised the 36-Item Short Form Survey (SF-36) as a measure of HRQoL. HRQoL determinants were grouped into nine themes. The most common determinant to be assessed was surgical technique (38/77, 49%) and patient satisfaction and experience of pain (10/77, 13%). HRQoL appeared to improve after surgery. Pain was a negative predictor of HRQoL.

CONCLUSION

Current data on the determinants of HRQoL in DCM are limited, contradictory and heterogeneous. Limitations of this systematic review include lack of distinction between DCM subtypes and heterogenous findings amongst the papers in which HRQoL is measured postoperatively or post-diagnosis. This highlights the need for greater standardisation in DCM research to allow further synthesis. Studies of greater precision are necessary to account for HRQoL being complex, multi-factorial and both time and context dependent.

Patients with radiculopathy have worse baseline disability and greater improvements following anterior cervical discectomy and fusion compared to patients with myelopathy

BACKGROUND CONTEXT

Anterior cervical discectomy and fusion (ACDF) is commonly performed in patients with radiculopathy and myelopathy. Although the goal of surgery in patients with radiculopathy is to improve function and reduce pain, patients with myelopathy undergo surgery to halt disease progression. Although the expectations between these preoperative diagnoses are generally understood to be disparate by spine surgeons, there is limited literature demonstrating their discordant outcomes.

PURPOSE

To compare improvements in patient reported outcome measures (PROMs) for patients undergoing ACDF for myelopathy or radiculopathy. Secondarily, we analyzed the proportion of patients who attain the minimum clinically important difference (MCID) postoperatively using thresholds derived from radiculopathy, myelopathy, and mixed cohort studies.

STUDY DESIGN/SETTING

Single institution retrospective cohort study PATIENT SAMPLE: Patients undergoing primary, elective ACDF with a preoperative diagnosis of radiculopathy or myelopathy and a complete set of preoperative and one-year postoperative PROMs.

OUTCOME MEASURES

Outcome measures included the following PROMs: Short-Form 12 Physical Component (PCS-12) and Mental Component (MCS-12) scores, the Visual Analog Scale (VAS) Arm score, and the Neck Disability Index (NDI). Hospital readmissions and revision surgery were also collected and evaluated.

METHODS

Patients undergoing an ACDF from 2014 to 2020 were identified and grouped based on preoperative diagnosis (radiculopathy or myelopathy). We utilized "general MCID" thresholds from a cohort of patients with degenerative spine conditions, and "specific MCID" thresholds generated from cohorts of patients with myelopathy or radiculopathy, respectively. Multivariate linear regressions were performed for delta (∆) PROMs and multivariate logistic regressions were performed for both general and specific MCID improvements.

RESULTS

A total of 798 patients met inclusion criteria. Patients with myelopathy had better baseline function and arm pain (MCS-12: 49.6 vs 47.6, p=.018; VAS Arm: 3.94 vs 6.02, p<.001; and NDI: 34.1 vs 41.9, p<.001), were older (p<.001), had more comorbidities (p=.014), more levels fused (p<.001), and had decreased improvement in PROMs following surgery compared to patients with radiculopathy (∆PCS-12: 4.76 vs 7.21, p=.006; ∆VAS Arm: -1.69 vs -3.70, p<.001; and ∆NDI: -11.94 vs -18.61, p<.001). On multivariate analysis, radiculopathy was an independent predictor of increased improvement in PCS-12 (β=2.10, p=.019), ∆NDI (β=-5.36, p<.001), and ∆VAS Arm (β=-1.93, p<.001). Radiculopathy patients were more likely to achieve general MCID improvements following surgery (NDI: Odds ratio (OR): 1.42, p=.035 and VAS Arm: OR: 2.98, p<.001), but there was no difference between patients with radiculopathy or myelopathy when using radiculopathy and myelopathy specific MCID thresholds (MCS-12: p=.113, PCS-12: p=.675, NDI: p=.108, and VAS Arm: p=.314).

CONCLUSIONS

Patients undergoing ACDF with myelopathy or radiculopathy represent two distinct patient populations with differing treatment indications and clinical outcomes. Compared to radiculopathy, patients with myelopathy have better baseline function, decreased improvement in PROMs, and are less likely to reach MCID using general threshold values, but there is no difference in the proportion reaching MCID when using specific threshold values.

LEVEL OF EVIDENCE

IRB.

Technical Aspects of Intra-Operative Ultrasound for Spinal Cord Injury and Myelopathy: A Practical Review

OBJECTIVES

To compile intra-operative techniques, established imaging parameters, available equipment and software, and clinical applications of intraoperative ultrasound imaging (IOUSI) for spinal cord injury (SCI) and myelopathy.

METHODS

PubMed and Google Scholar were searched for relevant articles. The articles were reviewed and selected by 2 independent researchers. After article selection, data were extracted and summarized into research domains. PRISMA systematic review process was followed.

RESULTS

Of the 2477 articles screened, 16 articles met the inclusion criteria. In patients with SCI and myelopathy, common quantitative measurements obtained using IOUSI were noted: 1) ultrasound elastography, 2) midsagittal anteroposterior diameter, 3) transverse, 4) transverse diameter, 5) maximum spinal cord compression, and 6) compression ratioTo ensure adequate decompression and to look for residual compression, the lateral and the craniocaudal margins of the laminectomy site were inspected in both axial and sagittal planes. In instances where quantitative assessment was not possible, cord decompression and degree of residual compression were gauged by inspecting the interface between the ventral border of the spinal cord and any potentially compressive elements, and by searching for symmetric and rhythmic cerebrospinal fluid pulsations. Use of contrast-enhanced ultrasoundand molecular imaging are additional advances in objective assessments for SCI and myelopathy.

CONCLUSIONS

This review outlines the potential of IOUSI in patients presenting with SCI and myelopathy. Moreover, by identifying potential for inter-operator variability in certain subjective measurements, we illustrate the need for further research to quantify and standardize those assessments.

Clinically meaningful improvement in disabilities of arm, shoulder, and hand (DASH) following cervical spine surgery

BACKGROUND CONTEXT

Patients with cervical spine disease suffer from upper limb disability. At present, no clinical benchmarks exist for clinically meaningful change in the upper limb function following cervical spine surgery.

PURPOSE

Primary: to establish clinically meaningful metrics; the minimal clinically important difference (MCID) and substantial clinical benefit (SCB) of upper limb functional improvement in patients following cervical spine surgery. Secondary: to identify the prognostic factors of MCID and SCB of upper limb function following cervical spine surgery.

STUDY DESIGN

Retrospective cohort study.

PATIENT SAMPLE

Adult patients ≥18 years of age who underwent cervical spine surgery from 2012 to 2016.

OUTCOME MEASURES

Patient-reported outcomes: Neck disability index (NDI) and Disabilities of Arm, Shoulder, and Hand (DASH).

METHODS

MCID was defined as minimal improvement and SCB as substantial improvement in the DASH score at last follow-up. The anchor-based methods (ROC analyses) defined optimal MCID and SCB thresholds with area under curve (AUC) in discriminating improved vs. non-improved patients. The MCID was also calculated by distribution-based methods: half standard-deviation (0.5-SD) and standard error of the mean (SEM) method. A multivariable logistic regression evaluated the impact of baseline factors in achieving the MCID and SCB in DASH following cervical spine surgery.

RESULTS

Between 2012 and 2016, 1,046 patients with average age of 57±11.3 years, 53% males, underwent cervical spine surgery. Using the ROC analysis, the threshold for MCID was -8 points with AUC of 0.73 (95% CI: 0.67-0.79) and the SCB was -18 points with AUC of 0.88 (95% confidence interval [CI]: 0.85-0.91). The MCID was -11 points by 0.5-SD and -12 points by SEM-method. On multivariable analysis, patients with myelopathy had lower odds of achieving MCID and SCB, whereas older patients and those with ≥6 months duration of symptoms had lower odds of achieving DASH MCID and SCB respectively.

CONCLUSIONS

In patients undergoing cervical spine surgery, MCID of -8 points and SCB of -18 points in DASH improvement may be considered clinically significant. These metrics may enable evaluation of minimal and substantial improvement in the upper extremity function following cervical spine surgery.

Patient-reported Data as Predictors of Surgical Outcome in Patients With Degenerative Cervical Myelopathy: Analysis of a National Multicenter Dataset

STUDY DESIGN

Retrospective study design on prospectively collected registry data.

OBJECTIVE

To investigate whether improvement after surgery for degenerative cervical myelopathy is associated with preoperative disease severity and to identify predictors of outcome.

SUMMARY OF BACKGROUND DATA

Degenerative cervical myelopathy is the most common cause of spinal cord compromise in adults and surgery is often the treatment of choice. Identifying predictors may help to improve patient selection.

MATERIALS AND METHODS

This nationwide study from the Swedish spine registry included 901 patients treated surgically for degenerative cervical myelopathy. To investigate improvement in different disease severity groups, the individuals were divided into quartiles based on their preoperative European Myelopathy Scale (EMS) and EuroQol-5 Dimension (EQ-5D) index. Statistical analyses were made with analysis of variance, χ 2 , McNemar, and t tests. Multivariable linear or logistic regression was used to identify predictors for one-year improvement in EMS and EQ-5D index, and satisfaction at one year. In the regressions, the patient-reported outcome measures were dichotomized at their median, except improvement in EMS.

RESULTS

All patient-reported outcome measures improved from baseline to the one-year follow-up ( P <0.001). Statistically significant outcome improvements were seen in all disease severity groups. Preoperative low EMS (β=-1.37, P <0.001), long walking distance (<500 vs. >500 m; β=0.44, P =0.030), and low NDI (β=-0.43, P =0.048) were independent predictors of improvement in EMS. R2 was 0.11 for the multivariable model. Preoperative low EQ-5D index (odds ratio=0.11; 95% confidence interval: 0.07-0.16) and low NDI (0.56; 0.36-0.88) were independent predictors of improvement in EQ-5D index. Preoperative high EMS (1.86; 1.20-2.90) and shorter arm pain duration [<12 vs. >12 months (0.54; 0.33-0.88)] were independent predictors of satisfaction.

CONCLUSIONS

Postoperative improvement was seen over the whole range of disease severity. Disease severity, symptom duration, and walking distance were predictors of outcome in patients treated surgically for degenerative cervical myelopathy.

LEVEL OF EVIDENCE

III.

Comparing Combined Anterior and Posterior to Posterior-Only Decompression and Fusion Crossing the Cervico-Thoracic Junction in Octogenarians

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

The purpose of the study was to compare early complication, morbidity and mortality risks associated with fusion surgery crossing the cervico-thoracic junction in patients aged over 80 years undergoing combined anterior and posterior approach versus a posterior-only approach.

METHODS

We retrospectively identified octogenarian patients with myelopathy who underwent fusion crossing the cervico-thoracic junction. Patient demographics, Nurick score, surgical characteristics, complications, hospital course, early outcome and 90-day mortality were collected. Comorbidities were classified using the age-adjusted Charlson Comorbidity Index (AACCI). Radiographic measurements for deformity correction included the C2-C7 sagittal Cobb angle, C2-7 sagittal vertical axis and T1 slope pre- and postoperatively.

RESULTS

Out of 8,521 surgically treated patients, 12 octogenarian patients had a combined anterior and posterior approach (AP group) and 14 were treated from posterior-only (P group). Mean age was 81.4 ± 1.2 and 82.5 ± 2.7 years, respectively. There was no significant difference in Nurick scores between the groups (P > 0.05). The major complication risk in the AP group was significantly higher, requiring PEG tube placement due to severe dysphagia in 4 patients (33%) compared to none in the P group. A greater improvement in cervical lordosis could be achieved through a combined approach. The 90-day mortality risk was 8% for the AP group and 0% for the P group.

CONCLUSIONS

A combined anterior and posterior approach is associated with a significantly higher major complication rate and can result in severe dysphagia requiring PEG tube placement in one-third of patients over 80 years of age.

Correlation of the Modified Japanese Orthopedic Association With Functional and Quality-of-Life Outcomes After Surgery for Degenerative Cervical Myelopathy: A Quality Outcomes Database Study

BACKGROUND

The modified Japanese Orthopedic Association (mJOA) score is a widely used and validated metric for assessing severity of myelopathy. Its relationship to functional and quality-of-life outcomes after surgery has not been fully described.

OBJECTIVE

To quantify the association of the mJOA with the Neck Disability Index (NDI) and EuroQol-5 Dimension (EQ-5D) after surgery for degenerative cervical myelopathy.

METHODS

The cervical module of the prospectively enrolled Quality Outcomes Database was queried retrospectively for adult patients who underwent single-stage degenerative cervical myelopathy surgery. The mJOA score, NDI, and EQ-5D were assessed preoperatively and 3 and 12 months postoperatively. Improvement in mJOA was used as the independent variable in univariate and multivariable linear and logistic regression models.

RESULTS

Across 14 centers, 1121 patients were identified, mean age 60.6 ± 11.8 years, and 52.5% male. Anterior-only operations were performed in 772 patients (68.9%). By univariate linear regression, improvements in mJOA were associated with improvements in NDI and EQ-5D at 3 and 12 months postoperatively (all P < .0001) and with improvements in the 10 NDI items individually. These findings were similar in multivariable regression incorporating potential confounders. The Pearson correlation coefficients for changes in mJOA with changes in NDI were -0.31 and -0.38 at 3 and 12 months postoperatively. The Pearson correlation coefficients for changes in mJOA with changes in EQ-5D were 0.29 and 0.34 at 3 and 12 months.

CONCLUSION

Improvements in mJOA correlated weakly with improvements in NDI and EQ-5D, suggesting that changes in mJOA may not be a suitable proxy for functional and quality-of-life outcomes.

Current treatments after spinal cord injury: Cell engineering, tissue engineering, and combined therapies

Both traumatic and non-traumatic spinal cord injuries (SCIs) can be categorized as damages done to our central nervous system (CNS). The patients' physical and mental health may suffer greatly because of traumatic SCI. With the widespread use of motor vehicles and increasingly aged population, the occurrence of SCI is more frequent than before, creating a considerable burden to global public health. The regeneration process of the spinal cord is hampered by a series of events that occur following SCI like edema, hemorrhage, formation of cystic cavities, and ischemia. An effective strategy for the treatment of SCI and functional recovery still has not been discovered; however, recent advances have been made in bioengineering fields that therapies based on cells, biomaterials, and biomolecules have proved effective in the repair of the spinal cord. In the light of worldwide importance of treatments for SCI, this article aims to provide a review of recent advances by first introducing the physiology, etiology, epidemiology, and mechanisms of SCI. We then put emphasis on the widely used clinical treatments and bioengineering strategies (cell-based, biomaterial-based, and biomolecule-based) for the functional regeneration of the spinal cord as well as challenges faced by scientists currently. This article provides scientists and clinicians with a comprehensive outlook on the recent advances of preclinical and clinical treatments of SCI, hoping to help them find keys to the functional regeneration of SCI.

Prognostic Factors Impacting Surgical Outcomes in Patients With Cervical Spondylotic Myelopathy

The purpose of surgical decompression in patients who have CSM is to stop the progression of symptoms and hopefully improve function. It is critical to understand prognostic factors that affect the outcome. Factors intrinsic to the patient that can adversely affect outcomes include diabetes, older age, tobacco use, the presence of mental health disease, and obesity. MRI imaging findings of T2 hyperintensity and clinical duration and severity of symptoms is also associated with poorer outcomes. Patients should be counseled regarding the efficacy of decompressive procedures for CSM and given realistic expectations based on their unique biophysical profiles.

The Natural History of Degenerative Cervical Myelopathy

Degenerative cervical myelopathy (DCM) is the most frequent cause of spinal cord dysfunction and injury in the adult population and leads to significant loss of quality of life and economic impact from its associated medical care expenditures and loss of work. Surgical intervention is recommended for patients manifesting progressing neurological signs and symptoms of myelopathy, but the optimal management in individuals who have mild and clinically stable disease manifestations is controversial. Understanding the natural history of DCM is, thus, important in assessing patients and identifying those most appropriately indicated for surgical management. Despite the attempts to rigorously perform studies of the natural history of these patients, most published investigations suffer from methodological weaknesses or are underpowered to provide definitive answers. Investigations of particular patient subsets, however, provide some clinical guidance as to which patients stand most to benefit from surgery, and these may include those with lower baseline mJOA scores, evidence of segmental hypermobility, cord signal changes on MRI, abnormal somatosensory or motor-evoked potentials, or the presence of certain inflammatory markers. Clinicians should assess patients with mild myelopathy and those harboring asymptomatic cervical spinal cord compression individually when making treatment decisions and an understanding of the various factors that may influence natural history may aid in identifying those best indicated for surgery. Further investigations will likely identify how variables that affect natural history can be used in devising more precise treatment algorithms.

Review of Prospective Trials for Degenerative Cervical Myelopathy

Degenerative cervical myelopathy (DCM) is the leading cause of spinal cord dysfunction in adults. DCM refers to a collection of degenerative conditions that cause the narrowing of the cervical canal resulting in neurological dysfunction. A lack of high-quality studies and a recent increase in public health awareness has led to numerous prospective studies evaluating DCM. Studies evaluating the efficacy of surgical intervention for DCM can be characterized by the presence (comparative) or absence (noncomparative) of a nonoperative control group. Noncomparative studies predominate due to concerns regarding treatment equipoise. Comparative studies have been limited by methodological issues and have not produced consistent findings. More recent noncomparative studies have established the safety and efficacy of surgical intervention for DCM, including mild myelopathy. The optimal surgical intervention for DCM remains controversial. A recent randomized clinical trial comparing dorsal and ventral techniques found similar improvements in patient-reported physical function at early follow-up. Recent prospective studies have enriched our understanding of DCM and helped guide current treatment recommendations.

Degenerative cervical myelopathy education in UK medical schools: a national cross-sectional survey of medical students

INTRODUCTION

Degenerative cervical myelopathy (DCM) is a common and progressive neurological condition caused by injury of the cervical spinal cord by degenerative spinal pathology. Delayed diagnosis leading to avoidable and irreversible disability is a major current problem limiting patient outcomes. Lack of sufficient representation of DCM in undergraduate and postgraduate medical curricula may contribute to poor recognition of DCM by non-specialist doctors. The objective of this study was to assess the DCM teaching provision in UK medical schools and the DCM knowledge of UK medical students.

METHODS

UK medical students completed a web-based survey distributed nationally through university social media pages, university email bulletins and the national student network of Myelopathy.org. The survey comprised a 19-item questionnaire capturing data on student demographics, myelopathy teaching and myelopathy knowledge. Advertisements were repeated monthly over a 12-month recruitment period and participation was incentivised by entry into an Amazon voucher prize draw. Ethical approval for the study was granted by the Psychology Research Ethics Committee, University of Cambridge (PRE.2018.099).

RESULTS

A total of 751 medical students from 32 British medical schools completed the survey. Medical students from all year groups participated. Most students (520; 72%) had not received any medical school teaching about DCM. When students had received DCM teaching, the duration of teaching was minimal (75% < 1 h). A total of 350 students (47%) reported conducting private study on DCM. Modal student self-rating of their own knowledge of DCM was 'terrible' (356; 47%). There was no correlation between a student's subjective rating of their knowledge and their answers to objective questions. A total of 723 (96%) of students expressed interest in learning more about DCM, with lectures the preferred format.

CONCLUSIONS

DCM appears to be a neglected condition in medical education which has implications for clinical practice. However, student enthusiasm to undertake private study suggests future teaching interventions will be well-received. Future work is necessary to characterise the format of DCM teaching that is most effective and to subsequently measure how educational interventions translate into clinical benefits.

Operative treatment outcomes for adult cervical deformity: a prospective multicenter assessment with mean 3-year follow-up

OBJECTIVE

Adult cervical deformity (ACD) has high complication rates due to surgical complexity and patient frailty. Very few studies have focused on longer-term outcomes of operative ACD treatment. The objective of this study was to assess minimum 2-year outcomes and complications of ACD surgery.

METHODS

A multicenter, prospective observational study was performed at 13 centers across the United States to evaluate surgical outcomes for ACD. Demographics, complications, radiographic parameters, and patient-reported outcome measures (PROMs; Neck Disability Index, modified Japanese Orthopaedic Association, EuroQol-5D [EQ-5D], and numeric rating scale [NRS] for neck and back pain) were evaluated, and analyses focused on patients with ≥ 2-year follow-up.

RESULTS

Of 169 patients with ACD who were eligible for the study, 102 (60.4%) had a minimum 2-year follow-up (mean 3.4 years, range 2-8.1 years). The mean age at surgery was 62 years (SD 11 years). Surgical approaches included anterior-only (22.8%), posterior-only (39.6%), and combined (37.6%). PROMs significantly improved from baseline to last follow-up, including Neck Disability Index (from 47.3 to 33.0) and modified Japanese Orthopaedic Association score (from 12.0 to 12.8; for patients with baseline score ≤ 14), neck pain NRS (from 6.8 to 3.8), back pain NRS (from 5.5 to 4.8), EQ-5D score (from 0.74 to 0.78), and EQ-5D visual analog scale score (from 59.5 to 66.6) (all p ≤ 0.04). More than half of the patients (n = 58, 56.9%) had at least one complication, with the most common complications including dysphagia, distal junctional kyphosis, instrumentation failure, and cardiopulmonary events. The patients who did not achieve 2-year follow-up (n = 67) were similar to study patients based on baseline demographics, comorbidities, and PROMs. Over the course of follow-up, 23 of the total 169 enrolled patients were reported to have died. Notably, these represent all-cause mortalities during the course of follow-up.

CONCLUSIONS

This multicenter, prospective analysis demonstrates that operative treatment for ACD provides significant improvement of health-related quality of life at a mean 3.4-year follow-up, despite high complication rates and a high rate of all-cause mortality that is reflective of the overall frailty of this patient population. To the authors' knowledge, this study represents the largest and most comprehensive prospective effort to date designed to assess the intermediate-term outcomes and complications of operative treatment for ACD.

Determining the time frame of maximum clinical improvement in surgical decompression for cervical spondylotic myelopathy when stratified by preoperative myelopathy severity: a cervical Quality Outcomes Database study

OBJECTIVE

While surgical decompression is an important treatment modality for cervical spondylotic myelopathy (CSM), it remains unclear if the severity of preoperative myelopathy status affects potential benefit from surgical intervention and when maximum postoperative improvement is expected. This investigation sought to determine if retrospective analysis of prospectively collected patient-reported outcomes (PROs) following surgery for CSM differed when stratified by preoperative myelopathy status. Secondary objectives included assessment of the minimal clinically important difference (MCID).

METHODS

A total of 1151 patients with CSM were prospectively enrolled from the Quality Outcomes Database at 14 US hospitals. Baseline demographics and PROs at baseline and 3 and 12 months were measured. These included the modified Japanese Orthopaedic Association (mJOA) score, Neck Disability Index (NDI), quality-adjusted life-years (QALYs) from the EQ-5D, and visual analog scale from the EQ-5D (EQ-VAS). Patients were stratified by preoperative myelopathy severity using criteria established by the AO Spine study group: mild (mJOA score 15-17), moderate (mJOA score 12-14), or severe (mJOA score < 12). Univariate analysis was used to identify demographic variables that significantly varied between myelopathy groups. Then, multivariate linear regression and linear mixed regression were used to model the effect of severity and time on PROs, respectively.

RESULTS

For NDI, EQ-VAS, and QALY, patients in all myelopathy cohorts achieved significant, maximal improvement at 3 months without further improvement at 12 months. For mJOA, moderate and severe myelopathy groups demonstrated significant, maximal improvement at 3 months, without further improvement at 12 months. The mild myelopathy group did not demonstrate significant change in mJOA score but did maintain and achieve higher PRO scores overall when compared with more advanced myelopathy cohorts. The MCID threshold was reached in all myelopathy cohorts at 3 months for mJOA, NDI, EQ-VAS, and QALY, with the only exception being mild myelopathy QALY at 3 months.

CONCLUSIONS

As assessed by statistical regression and MCID analysis, patients with cervical myelopathy experience maximal improvement in their quality of life, neck disability, myelopathy score, and overall health by 3 months after surgical decompression, regardless of their baseline myelopathy severity. An exception was seen for the mJOA score in the mild myelopathy cohort, improvement of which may have been limited by ceiling effect. The data presented here will aid surgeons in patient selection, preoperative counseling, and expected postoperative time courses.

Brain connectivity markers in degenerative cervical myelopathy patients with depression for predicting the prognosis following decompression surgery

OBJECTIVE

To determine if brain functional connectivity (FC) is associated with the prognosis in depressed degenerative cervical myelopathy patients (DCM) and to investigate the possible brain functional mechanism.

METHODS

Resting-state fMRI scans and peripheral blood cell counts from 33 depressed DCM patients, 33 age and gender-matched DCM patients without depression were analyzed. All patients were evaluated using Japanese Orthopedic Association score before and 6 weeks after decompression surgery. JOA recovery rate was calculated to assess the functional recovery for DCM patients. For each participant, seed-based functional connectivity maps based on sub-regions centered on the striatum were computed and compared between groups. Pearson correlations were performed to explore the relationships between clinical measures and brain alterations in depressed DCM patients. To further investigate the relationships between brain alterations and clinical measures in depressed DCM patients, mediation analyses were performed. Flow cytometry was also performed on the three of the 33 depressed DCM patients, and the results were analyzed.

RESULTS

In comparison to patients without depression, DCM patients exhibited lower FC between the dorsal caudate (dC) and the inferior frontal operculum, which is located in the dorsal lateral prefrontal cortex (dlPFC). In depressed DCM patients, the altered dC-dlPFC FC was associated with inflammation as determined by the neutrophils/lymphocyte's ratio and prognosis. Furthermore, the mediation analysis demonstrated that the dC-dlPFC FC mediated the effect of inflammation on prognosis. The outcomes of our three cases followed a similar pattern to these findings.

CONCLUSION

In conclusion, our findings imply that inflammation slowed the functional recovery in depressed DCM patients through the striatal-frontal FC pathway.

Does Age and Medicare Status Affect Clinical Outcomes in Patients Undergoing Anterior Cervical Discectomy and Fusion?

OBJECTIVE

The objective of this study was to determine if Medicare status and age affect clinical outcomes following anterior cervical discectomy and fusion.

METHODS

Patients who underwent cervical discectomy and fusion between 2014 and 2020 with complete preoperative and 1-year postoperative patient-reported outcome measures (PROMs) were grouped based on Medicare status and age: no Medicare under 65 years (NM < 65), Medicare under 65 years (M < 65), no Medicare 65 years or older (NM ≥ 65), and Medicare 65 years or older (M ≥ 65). Multivariate regression for ΔPROMs (Δ: postoperative minus preoperative) controlled for confounding differences between groups. Significant was set at P < 0.05.

RESULTS

A total of 1288 patients were included, with each group improving in the visual analog score (VAS) Neck (all, P < 0.001), VAS Arm (M < 65: P = 0.003; remaining groups: P < 0.001), and Neck Disability Index (M < 65: P = 0.009; remaining groups: P < 0.001) following surgery. Only M < 65 did not significantly improve in the Physical Component Score (PCS-12) and modified Japanese Orthopaedic Association (mJOA) score (P = 0.256 and P = 0.092, respectively). When comparing patients under 65 years, non-Medicare patients had better preoperative PCS-12 (P < 0.001), Neck Disability Index (P < 0.001), and modified Japanese Orthopaedic Association (P < 0.001), as well as better postoperative values for all PROMs (P < 0.001), but there were no differences in ΔPROMs. Multivariate analysis identified M < 65 to be an independent predictor of decreased improvement in ΔPCS-12 (β = -4.07, P = 0.015), ΔVAS Neck (β = 1.17, P = 0.010), and ΔVAS Arm (β = 1.15, P = 0.025) compared to NM < 65.

CONCLUSIONS

Regardless of age and Medicare status, all patients undergoing cervical discectomy and fusion had significant clinical improvement postoperatively. However, Medicare patients under age 65 have a smaller magnitude of improvement in PROMs.

Degenerative Cervical Myelopathy: Evaluation and Management

Degenerative cervical myelopathy is most commonly caused by cervical spondylosis, with a predominant elderly population, and is the most common cause of spinal cord impairment. Patients typically present with gait dysfunction, hand impairment, and/or the presence of long tract signs: clonus, Hoffman sign, Babinski sign, or inverted radial reflexes. One of the key surgical strategies is deciding an approach, which is based on patient characteristics and cause of pathologic condition. Without operative intervention, there is a high rate of neurological decline. Most surgeons recommended surgical treatment given the favorable outcomes and well understood natural history of disease.

Intervertebral kinematics during neck motion 6.5 years after fusion and artificial disc replacement

BACKGROUND

Arthroplasty with artificial disc replacement for surgical treatment of cervical spine degeneration was introduced with the notion that motion-preserving approaches would prevent development of adjacent segment disease. Though clinical outcomes favor arthroplasty over the commonly used anterior cervical discectomy with fusion approach, clinical studies confirming the biomechanical basis of these results are lacking. The aim of this study was to compare intervertebral kinematics between arthroplasty and fusion patients 6.5 years post-surgery during physiological motion of the neck.

METHODS

Using a biplane dynamic X-ray system, computed tomography imaging and model based tracking algorithms, three dimensional intervertebral kinematics were measured during neck axial rotation and extension in 14 patients treated for cervical radiculopathy with fusion (n = 8) or arthroplasty (n = 6). The measurements were performed at 2-year (baseline) and 6.5 year post-surgical time points, with the main interest being in the interaction between surgery types and time points. 3 translations and 3 rotations were investigated for the index (C5C6), and upper- (C4C5) and lower adjacent levels (C6C7).

FINDINGS

Surgery-time interaction was significant for axial rotation (P < 0.04) and flexion-extension rotation (P < 0.005) in C4C5 during neck axial rotation, left-right translation (P < 0.04) in C5C6 and anterior-posterior translation in C6C7 (P < 0.04) during neck extension. In contrast with the expectations, axial rotation and flexion-extension decreased in C4C5 during neck rotation and anterior-posterior translation decreased in C6C7 during neck extension for fusion.

INTERPRETATION

The findings do not support the notion that adjacent segment motion increases after fusion.

Predictors of home discharge after scheduled surgery for degenerative cervical myelopathy

OBJECTIVE

Degenerative cervical myelopathy (DCM) is an important public health issue. Surgery is the mainstay of treatment for moderate and severe DCM. Delayed discharge of patients after DCM surgery is associated with increased healthcare costs. There is a paucity of data regarding predictive factors for discharge destination after scheduled surgery for patients with DCM. The purpose of this study was to identify factors predictive of home versus nonhome discharge after DCM surgery.

METHODS

Patients undergoing scheduled DCM surgery who had been enrolled in a prospective DCM substudy of the Canadian Spine Outcomes and Research Network registry between January 2015 and October 2020 were included in this retrospective analysis. Patient data were evaluated to identify potential factors predictive of home discharge after surgery. Logistic regression was used to identify independent factors predictive of home discharge. A multivariable model was then used as a final model.

RESULTS

Overall, 639 patients were included in the initial analysis, 543 (85%) of whom were discharged home. The mean age of the entire cohort was 60 years (SD 11.8 years), with a BMI of 28.9 (SD 5.7). Overall, 61.7% of the patients were female. The mean length of stay was 2.72 days (SD 1.7 days). The final internally validated bootstrapped multivariable model revealed that younger age, higher 9-Item Patient Health Questionnaire score, lower Neck Disability Index scores, fewer operated levels, mJOA scores indicating mild disease, anterior cervical discectomy and fusion procedure, and no perioperative adverse effects were predictive of home discharge.

CONCLUSIONS

Younger age, less neck-related disability, fewer operated levels, more significant depression, less severe myelopathy, anterior cervical discectomy and fusion procedure, and no perioperative adverse effects are predictive of home discharge after surgery for DCM. These factors can help to guide clinical decision-making and optimize postoperative care pathways.

Acute Systemic White Blood Cell Changes following Degenerative Cervical Myelopathy (DCM) in a Mouse Model

Degenerative cervical myelopathy (DCM) is caused by age-related degeneration of the cervical spine, causing chronic spinal cord compression and inflammation. The aim of this study was to assess whether the natural progression of DCM is accompanied by hematological changes in the white blood cell composition. If so, these changes can be used for diagnosis complementing established imaging approaches and for the development of treatment strategies, since peripheral immunity affects the progression of DCM. Gradual compression of the spinal cord was induced in C57B/L mice at the C5-6 level. The composition of circulating white blood cells was analyzed longitudinally at four time points after induction of DCM using flow cytometry. At 12 weeks, serum cytokine levels were measured using a Luminex x-MAP assay. Neurological impairment in the mouse model was also assessed using the ladder walk test and CatWalk. Stepping function (* p < 0.05) and overground locomotion (*** p < 0.001) were impaired in the DCM group. Importantly, circulating monocytes and T cells were affected primarily at 3 weeks following DCM. T cells were two-fold lower in the DCM group (*** p < 0.0006), whereas monocytes were four-fold increased (*** p < 0.0006) in the DCM compared with the sham group. Our data suggest that changes in white blood cell populations are modest, which is unique to other spinal cord pathologies, and precede the development of neurobehavioral symptoms.

Comparative analysis of the biomechanics of anterior cervical discectomy and fusion with multiple segmental plates fixation versus single multilevel plate fixation: a finite element study

BACKGROUND

This study aimed to compare the biomechanical differences between anterior cervical discectomy and fusion (ACDF) with multiple-level separate plates and conventional long plates by using finite element analysis.

METHODS

The following four finite element models were created to simulate various fixations: (1) C4-6 ACDF with multiple plates, (2) C4-6 ACDF with a single plate, (3) C3-6 ACDF with multiple plates, and (4) C3-6 ACDF with a single plate. The maximum Von-mises stress of the cage and fixation, compressive force of the adjacent intervertebral discs and range of motion (ROM) of different segments in the four models were calculated and analyzed.

RESULTS

For C4-6 ACDF, the maximum Von-mises stress of the cage and fixation was lower in the multiple plate fixation model in all motion states. Similarly, for the C3-6 ACDF models, the peak stress of the C3-4 and C5-6 cages was lower with multiple plates fixation in all motions but the stress of the C4-5 cage in the multiple plates model was slightly higher in flexion, bending and rotation. Besides, applying multiple plates in C3-6 ACDF models resulted in a decreased maximum stress of the fixation under different motions except for bending. In both the C4-6 ACDF and C3-6 ACDF models, the ROM values of the adjacent motion segments were lower in the multiple plates models in extension, bending and rotation. In the C4-6 ACDF models, the peak stress on the adjacent intervertebral discs in the multiple plates models was slightly smaller. In C3-6 ACDF models, the maximum stress on the adjacent intervertebral discs was larger in the single-plate model under flexion, bending and rotation movements.

CONCLUSION

Multiple plates fixation has a positive effect on increasing stiffness and maintaining the ROM of adjacent segments, indicating lower risk of construct failure and adjacent segment degeneration. Further studies are required to confirm its efficacy in clinical practice.

Change in Physical and Mental Quality-of-Life between the Short- and Mid-Term Periods after Cervical Laminoplasty for Cervical Spondylotic Myelopathy: A Retrospective Cohort Study with Minimum 5 Years Follow-up

The mid-term surgical outcomes of cervical spondylotic myelopathy (CSM), evaluated using the cervical Japanese Orthopedic Association (cJOA) score, are reported to be satisfactory. However, there remains room for improvement in quality-of-life (QOL), especially after short-term follow-up. We aimed to demonstrate changes in mental and physical QOL between short- and mid-term follow-ups and determine the predictive factors for deterioration of QOL. In this retrospective cohort study, 80 consecutive patients underwent laminoplasty for CSM. The outcome measures were Short Form-36 Physical Component Summary (PCS), Mental Component Summary (MCS), and cJOA scores. PCS and MCS scores were compared at the 2- and 5-year postoperative time points. Additionally, a multivariate logistic regression model was used to identify the predictive factors for deterioration. Significant factors in the logistic regression analysis were analyzed using receiver-operating characteristic curves. The results showed that MCS scores did not deteriorate after 2 years postoperatively (p = 0.912). Meanwhile, PCS significantly declined between 2 and 5 years postoperatively (p = 0.008). cJOA scores at 2 years postoperatively were significantly associated with PCS deterioration at 2-year follow-up. In conclusion, only physical QOL might show deterioration after short-term follow-up. Such deterioration is likely in patients with a cJOA score <13.0 at 2 years postoperatively.

Differences in postoperative quality of life in young, early elderly, and late elderly patients undergoing surgical treatment for degenerative cervical myelopathy

OBJECTIVE

Cervical spondylotic myelopathy (CSM) is a common progressive spine disorder affecting predominantly middle-aged and elderly populations. With increasing life expectancy, the incidence of CSM is expected to rise further. The outcomes of elderly patients undergoing CSM surgery and especially their quality of life (QOL) postoperatively remain undetermined. This study retrospectively reviewed patients to identify baseline differences and validated postoperative patient-reported outcome (PRO) measures in elderly patients undergoing CSM surgery.

METHODS

The multi-institutional, neurosurgery-specific NeuroPoint Quality Outcomes Database was queried to identify CSM patients treated surgically at the 14 highest-volume sites from January 2016 to December 2018. Patients were divided into three groups: young (< 65 years), early elderly (65-74 years), and late elderly (≥ 75 years). Demographic and PRO measures (Neck Disability Index [NDI] score, modified Japanese Orthopaedic Association [mJOA] score, EQ-5D score, EQ-5D visual analog scale [VAS] score, arm pain VAS, and neck pain VAS) were compared among the groups at baseline and 3 and 12 months postoperatively.

RESULTS

A total of 1151 patients were identified: 691 patients (60%) in the young, 331 patients (28.7%) in the early elderly, and 129 patients (11.2%) in the late elderly groups. At baseline, younger patients presented with worse NDI scores (p < 0.001) and lower EQ-5D VAS (p = 0.004) and EQ-5D (p < 0.001) scores compared with early and late elderly patients. No differences among age groups were found in the mJOA score. An improvement of all QOL scores was noted in all age groups. On unadjusted analysis at 3 months, younger patients had greater improvement in arm pain VAS, NDI, and EQ-5D VAS compared with early and late elderly patients. At 12 months, the same changes were seen, but on adjusted analysis, there were no differences in PROs between the age groups.

CONCLUSIONS

The authors' results indicate that elderly patients undergoing CSM surgery achieved QOL outcomes that were equivalent to those of younger patients at the 12-month follow-up.

Comparison of surgical outcomes of posterior surgeries between cervical spondylotic myelopathy and ossification of the posterior longitudinal ligament

STUDY DESIGN

Retrospective multicenter study.

OBJECTIVE

To compare the surgical outcomes and complications of posterior decompression between individuals with cervical spondylotic myelopathy (CSM) and those with ossification of the posterior longitudinal ligament (OPLL).

SETTING

Seventeen medical institutions in Japan.

METHODS

This study included 814 individuals with CSM (n = 636) and OPLL (n = 178) who underwent posterior decompression. Propensity score matching of the baseline characteristics was performed to compare surgical outcomes and perioperative complications between the CSM and OPLL groups.

RESULTS

Before propensity score matching, the OPLL group had higher percentage of male individuals, body mass index, and number of stenosis levels and longer duration of symptoms (P < 0.01, P < 0.01, P < 0.01, and P < 0.01, respectively). After matching, the baseline characteristics were comparable between the CSM (n = 98) and OPLL (n = 98) groups. The postoperative Japanese Orthopaedic Association (JOA) scores, preoperative-to-postoperative changes in the JOA scores, and JOA score recovery rates were not significantly different between the groups (P = 0.42, P = 0.47, and P = 0.09, respectively). The postoperative visual analog scale (VAS) score for neck pain and preoperative-to-postoperative changes in the VAS score for neck pain were not significantly different between the groups (P = 0.25 and P = 0.50, respectively). The incidence of perioperative complications was comparable between groups.

CONCLUSION

Neurological improvement and complication rates after surgery were comparable between individuals with CSM and those with OPLL, suggesting similar effectiveness and safety of posterior decompression for both conditions.

Utility of Diffusion and Magnetization Transfer MRI in Cervical Spondylotic Myelopathy: A Pilot Study

Diffusion tensor imaging (DTI) and magnetization transfer (MT) magnetic resonance imaging (MRI) can help detect spinal cord pathology, and tract-specific analysis of their parameters, such as fractional anisotropy (FA), mean diffusivity, axial diffusivity (AD), radial diffusivity (RD) and MT ratio (MTR), can give microstructural information. We performed the tract-based acquisition of MR parameters of three major motor tracts: the lateral corticospinal (CS), rubrospinal (RuS) tract, and lateral reticulospinal (RS) tract as well as two major sensory tracts, i.e., the fasciculus cuneatus (FC) and spinal lemniscus, to detect pathologic change and find correlations with clinical items. MR parameters were extracted for each tract at three levels: the most compressed lesion level and above and below the lesion. We compared the MR parameters of eight cervical spondylotic myelopathy patients and 12 normal controls and analyzed the correlation between clinical evaluation items and MR parameters in patients. RuS and lateral RS showed worse DTI parameters at the lesion level in patients compared to the controls. Worse DTI parameters in those tracts were correlated with weaker power grasp at the lesion level. FC and lateral CS showed a correlation between higher RD and lower FA and MTR with a weaker lateral pinch below the lesion level.